最近写了个小程序，计算出txt文件的字节数，并重新写入新的txt，使格式整齐。具体的要求如下：原有文件是用TAB键分割的，现不要分割符了，还有注意定长是按字节算的，也就是一个中文是两个字节，一个数字或字母是一个字节。字段都是定长的，不足右补空格。

开发环境是vs2008。txt文件内容如下：

39031687 上海高等教育普通全日制院校专业设置目录:1985-1986 -G649.285.1-63/S322
39000968 马克思恩格斯列宁斯大林***著作大辞典.1 A-61/001/1
01264804 马克思主义百科要览.2 A-61/002/2

计算3个字段的字节数，如果txt文件时4个以上字段，再增加即可：

---

        private int temp0 = 0, temp1 = 0, temp2 = 0;        //最终显示字段结果
        private int l0 = 0, l1 = 0, l2 = 0;                 //文件每个字段最长字节数
        private void Btn_OpenFile_Click(object sender, EventArgs e)
        {
            string FileName;
            if (this.openFileDialog1.ShowDialog() == DialogResult.OK)           //打开文件
            {
                FileName = this.openFileDialog1.FileName;
                if (FileName != "")
                {
                    string newValue = string.Empty;
                    using (StreamReader read = new StreamReader(FileName, Encoding.GetEncoding("gb2312")))      //中文
                    {
                        do
                        {
                            newValue = read.ReadLine();
                            if (newValue != null)
                            {
                                string[] line = newValue.Split('\t');                           //\t是以tab为分隔符
                                l0 = (System.Text.Encoding.Default.GetBytes(line[0])).Length;   //第一个字段
                                l1 = (System.Text.Encoding.Default.GetBytes(line[1])).Length;   //第二个字段
                                l2 = (System.Text.Encoding.Default.GetBytes(line[2])).Length;   //第三个字段
                                if (l0 > temp0)
                                {
                                    temp0 = l0;
                                }
                                if (l1 > temp1)
                                {
                                    temp1 = l1;
                                }
                                if (l2 > temp2)
                                {
                                    temp2 = l2;
                                }
                            }
                        }
                        while (newValue != null);
                    }
                }
                Tb_Show.Text = "文件中，三个字段的最大字节分别是："+temp0+","+temp1+","+temp2+"。";
            }
        }

---

写入新的文件，完成格式要求

---

            string FileName = openFileDialog1.FileName;
            if (FileName != "")
            {
                string newValue = string.Empty;
                using (StreamReader read = new StreamReader(FileName, Encoding.GetEncoding("gb2312")))
                {
                    do
                    {
                        newValue = read.ReadLine();
                        if (newValue != null)
                        {
                            int m0, m1, m2;
                            string[] line = newValue.Split('\t');
                            l0 = (System.Text.Encoding.Default.GetBytes(line[0])).Length;
                            l1 = (System.Text.Encoding.Default.GetBytes(line[1])).Length;
                            l2 = (System.Text.Encoding.Default.GetBytes(line[2])).Length;
                            m0 = temp0 - l0;
                            m1 = temp1 - l1;
                            m2 = temp2 - l2;
                            if (!File.Exists(Application.StartupPath + "\\new.txt"))        //文件保存在当前应用程序目录下，名字为new.txt
                            {
                                FileStream fs1 = new FileStream(Application.StartupPath + "\\new.txt", FileMode.Create, FileAccess.Write);
                                StreamWriter sw = new StreamWriter(fs1);
                                string s0 = line[0];
                                string s1 = line[1];
                                string s2 = line[2];
                                sw.Write(s0);
                                for (int i = 0; i < m0; i++)
                                {
                                    sw.Write("\0");
                                }
                                sw.Write(s1);
                                for (int j = 0; j < m1; j++)
                                {
                                    sw.Write("\0");
                                }
                                sw.Write(s2);
                                for (int k = 0; k < m2; k++)
                                {
                                    sw.Write("\0");
                                }
                                sw.Write("\r\n");
                                sw.Close();
                                fs1.Close();
                            }
                            else
                            {
                                StreamWriter sw2 = File.AppendText(Application.StartupPath + "\\new.txt");
                                m0 = temp0 - l0;
                                string s0 = line[0];
                                string s1 = line[1];
                                string s2 = line[2];
                                sw2.Write(s0);
                                for (int i = 0; i < m0; i++)
                                {
                                    sw2.Write("\0");
                                }
                                sw2.Write(s1);
                                for (int j = 0; j < m1; j++)
                                {
                                    sw2.Write("\0");
                                }
                                sw2.Write(s2);
                                for (int k = 0; k < m2; k++)
                                {
                                    sw2.Write("\0");
                                }
                                sw2.Write("\r\n");
                                sw2.Close();
                            }
                        }
                    }
                    while (newValue != null);
                }
            }
        }

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写的程序不足之处，请多多包涵,thanks...